Thermal processing torches, such as plasma arc torches, are widely used in the heating, cutting, gouging, and marking of materials. A plasma arc torch generally includes an electrode, a nozzle having a central exit orifice mounted within a torch body, electrical connections, passages for cooling, and passages for arc control fluids (e.g., plasma gas). A swirl ring can be used to control fluid flow patterns in the plasma chamber formed between the electrode and the nozzle. In operation, a plasma arc torch produces a plasma arc, which is a constricted jet of an ionized gas with high temperature and sufficient momentum to assist with removal of molten metal. Power used to operate plasma arc torches can be controlled by a power supply assembly of a plasma operating system. The power supply and/or metering console, which is often located distant relative to the torch (e.g., several feet or meters away), can include a plurality of electronic components configured to control and supply an operational current to the plasma arc torch, the gas flows provided to the plasma arc torch, and, in some cases, motion of the plasma arc torch. The power supply can include various types of components and systems to control the flow of gases to the torch, as well as to regulate the pressure of gases delivered to the torch.